Rotary pump for liquids or gases



Feb. 9 1926. y

S. MAROGER ROTARY PUMP FOR LIQDS OR GASES Filed Oct. 27. 1924 PATENTOFFICE.

SAMUEL MAROGER, OF NIMES, FRANCE.

ROTARY PUMP FOR LIQUIIDS OR GASES.

Application filed October 27, 1924. Serial No. 746,106.

To all 'whom it lmay concern:

Be it known that I, SAMUEL MAnoonk, a citizen of the Republic ot'France, residing at 2G Rue Dhuoda, Nimes, Gard, France, have inventndnew and useful Improvements in Rotary Pumps l'or Liquids or Gases, ofwhich the following is a specilication.

Rotary pumps, of the screw type usually comprise a screw rotating in acylinder and a special device (star or toot-hed wheel) which preventsthe liquid which iills the pump from taking part in the rotary movementof the screw, so that the liquid moves in accordance with thegeneratrices ot' the cylinder which forms the body ot' the pump and itremains constantly imprisoned between the threads of the screw.

Such an arrangement is subject to the drawback that it complicates theinternal mechanism of the apparatus owing to the fact that special meansmust be provided tol prevent the liquid from participating in themovement ot the screw.

This invention relates to a pump of the type referred to which does notcomprise any special means for the purpose mentioned, apart from thebody of the pump itself and the screw, the screw being arranged in sucha manner that the helicoidal entrainment ot' the iuid (liquid or gas)cannot take place. The device presents the further advantages, owing tothe uses to which it can be put, of enabling large outputs to beobtained as well as of being capable ot' running at approximately thesame speeds as the motor to which the pump is coupled, the samearrangement being applicable for the purpose of obtaining high vacua orpressures.

The invention consists in mounting, in the body ot the pump, a drum ot'smaller diameter which constitutes the body of the driving screw and inplacing this drum eccentrically relative to the pump body in such amanner that they are tangential to each other, the said drum having ahelicoidal groove in which is fitted a helix ot corresponding pitch, butof the same diameter as the pump body, the helix being fitted in itsgroove with a certain amount of clearance in order to enable it to movetherein and to take up easily any wear which may arise.

In order to avoid leakage and to ensure tightness of the pump, it isnecessary that the thread ot the helix shall make a number ofrevolutions or fractions ot revolutions such that the same threadtouches the pumpbody at least twice. In the case of a pump having asingle thread, two revolutions are therefore necessary and the pump-body'must be made sufficiently long. It, however, two threads are provided,one and one half revolutions will be suilicient to ensure tightness, andby this means the length of the pump body necessary for a given outputcan be diminished.

The invention contemplates the formation of the body of the screw of aseries of discs, placed side by side, and mounted upon the same shaft,which is eccentric to the pumpbody, these discs having straight groovesof suitable inclination and corresponding to that of the thread of thescrew which it is' desired to obtain, and also the mounting of straightblades in these grooves in such a manner that they can move thereinindependently of each other, the entire device, while presenting thegeneral aspect of a screw and oii'ering the advantage that itsmanufacture and erection are simple, while its operation is consistent.

In the drawing, Fig. 1 is a transverse seetion of a rotary pumpconstructed according to the present invention. l

Figs. 2 and 8 are detail views showing, respectively, one of the discsshown in Fig. 1 and one of the blades intended to be mounted in thisdisc.

In the examples shown in Figs. 1 to 3, the pump-body 1 is provided atits extremities with admission and discharge nozzles 2 and 3 and hasbearings 4 for the reception of the shaft of the rotary member of thepump, these bearings being formed eccentrically relative to thepump-body 1. The rotary member comprises a series of disks l0 of smallerdiameter than the interior of the body of `he pump and placed side byside on the shaft 6 and, owing to the eccentrieity of the shaft 6, whichcan rotate in the bearings 4, the disks l0 are tangent to the bore ofthe body of the pump only along one of their generatriees. Athrust-bearing is formed at one of the extremities of the shaft 6, whilethe other extremity rotates in a stuffing box 7 which ensures a fluid tiht fit Upon the discs 10 there are ormed obliquely straight grooves 12,the sequence of which represents substantially the aspect of ahelicoidal groove formed of broken lines; and, iu the ease of twothreads, these grooves will be disposed inversely relative to the twoextremities of a diameter of each of the `ment of the helix.

discs, in such a manner that each of the extremities of' thegrooves ofone of them coincides with the extremity of a groove of the adjacentdisc. The blades 11 can be mounted in the grooves 12 and can move in thelatter, the face 13 of each'of said blades being formed in such a mannerthat it can bear exactly upon the bore of the body of the pump. Theblades are constantly pressed against the bore of the body of the; pumpby centrifugal force, so that any wear is automatically compensated. Theshaft 6 of the drum, being driven by the motor, the disks 10 comprisingthe rotary member and the blades 11 carried thereby are caused torotate. The fluid (gas or liquid) which fills the pump, cannot take partin the rotary movement of the helix formed by the blades 1l since thereis no room for the passage of such fluid at the line of tangency betweenthe disks 10 and the body '1 of' the pump, so that it can only followthe advancing move- The result is that the fluid taken in at theadmission nozzle 2 is forced out through the discharge vnozzle 3.

It is evident that certain modifications could be made in thisarrangement of rotary pump or that other systems of mounting the screwcould be devised without departing from the spirit of the invention.

I claim:

1. A rotary pump comprising in combination a pump-body, a drum mountedeccentrically in said pump-body, said drum having a helical groove, anda helix fitted in said groove, said helix being made in sections for thepurpose set forth.

2. A rotary pump comprising in combination a pump-body, a drum mountedeccentrically in said body so as to contact therewith along onegeneratrix alone, said drum having a plurality of helicoidal grooves,and a helix formed in sections fitted in each of said grooves.

3. A rotary pump comprising in combination a pump-body, a plurality ofi'discs mounted eccentrically in said body and contacting therewith alonga generati-ix, said discs having grooves, and blades fitted in saidgrooves and adapted to contact with the inner wall of said pump body.

4. A rotary pump comprising in combination a pump-body, a plurality ofdiscs mounted eccentrically in said body and contacting therewith alonga generatrix, said discs having straight grooves arranged obliquely, andblades fitted in said grooves and contacting with the inner Wall of saidpump body.

5. A rotary pump comprising in combination a pump-body, a shaft mountedeccentrically in said pump-body, a plurality of discs mountedconcentrically upon said shaft and of such diameter as to contact withsaid pump-body along one generatrix only, said discs having straightgrooves'arranged in such relativeformation as to form substantially ahelicoidal line, and blades fitted in said grooves.

SAMUEL MAROGER.

